关键词: 电子商务, 软时间窗, 退换货, 车辆路径问题（VRP）, 蚁群算法

Abstract: In order to integrate the forward and reverse logistics of logistics enterprises in the e-commerce environment, a vehicle path planning model with soft time windows and the return and replacement is established acording to the actual situation. An ant colony algorithm improved by the variable neighborhood search algorithm is designed to solve such problem. Based on the basic ant colony algorithm, the initial pheromone setting, state transition rules and pheromone update strategy are improved according to the characteristics of the problem. The variable neighborhood search algorithm is combined to improve the search ability of the algorithm. The proposed algorithm has better performance in the experiments of the relevant literature data, standard examples and the real data of enterprises. It is an effective algorithm for solving the proposed problem.

Key words: e-commerce, soft time windows, return and replacement, Vehicle Routing Problem（VRP）, ant colony algorithm